Application of microbial electrolysis cells to treat spent yeast from an alcoholic fermentation.

Abstract

Spent yeast (SY), a major challenge for the brewing industry, was treated using a microbial electrolysis cell to recover energy. Concentrations of SY from bench alcoholic fermentation and ethanol were tested, ranging from 750 to 1500mgCOD/L and 0 to 2400mgCOD/L respectively. COD removal efficiency (RE), coulombic efficiency (CE), coulombic recovery (CR), hydrogen production and current density were evaluated. The best treatment condition was 750mgCOD/LSY+1200mgCOD/L ethanol giving higher COD RE, CE, CR (90±1%, 90±2% and 81±1% respectively), as compared with 1500mgCOD/LSY (76±2%, 63±7% and 48±4% respectively); ethanol addition was significantly favorable (p value=0.011), possibly due to electron availability and SY autolysis. 1500mgCOD/LSY+1200mgCOD/L ethanol achieved higher current density (222.0±31.3A/m(3)) and hydrogen production (2.18±0.66 [Formula: see text] ) but with lower efficiencies (87±2% COD RE, 71.0±.4% CE). Future work should focus on electron sinks, acclimation and optimizing SY breakdown.

• Authors: Ornella Sosa-Hernández, Sudeep C Popat, Prathap Parameswaran, Gibrán Sidney Alemán-Nava, César I Torres, Germán Buitrón, Roberto Parra-Saldívar
• Journal: Bioresource technology (Bioresour Technol) Vol. 200 Pg. 342-9 (Jan 2016) ISSN: 1873-2976 [Electronic] England
• PMID: 26512857 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

Chemical References

• Ethanol
• Hydrogen

Topics

• Autolysis
• Bacteria (metabolism)
• Biological Oxygen Demand Analysis
• Electrolysis
• Electrons
• Equipment Design
• Ethanol (metabolism)
• Fermentation
• Hydrogen (chemistry)
• Hydrogen-Ion Concentration
• Temperature
• Yeasts